Integrated recording head with selective movement

ABSTRACT

A recording head for use in magnetic storage devices is disclosed. The recording head includes flexure assemblies that can be selectively and electrically charged to provide a motional force to selectively move the flexure assemblies and to cause corresponding movement of a transducer with to a surface of a magnetic medium.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.10/900,713, filed Jul. 27, 2004, now issued as U.S. Pat. No. 7,538,983,which claims the benefit of U.S. Provisional Patent Application Ser. No.60/490,750, filed Jul. 29, 2003, which are incorporated herein byreference in their entireties.

BACKGROUND

1. The Field of the Invention

The present invention generally relates to data storage on rotatingmagnetic storage devices. More specifically, the present inventionrelates to a rotating magnetic storage device having a recording headthat is bi-directionally controlled.

2. The Related Technology

During recent years, there has been a steady improvement in the volumeof data that can be stored on magnetic storage media, such as hard diskdrives used in computers. Today, a single 3.5 inch magnetic storage diskcan store twenty gigabytes or more of data. At the same time, storagecapacity per unit cost has fallen dramatically, which has enabledindividual users and enterprises to radically change the way in whichdata is recorded and stored. Indeed, the ability to store large volumesof data inexpensively has been a driving factor in the informationtechnology revolution during recent decades.

Conventional storage media include solid-state devices, drive arrays(RAID), single rotating magnetic disk drives, and removable opticalmedia. FIG. 1 is a graph that illustrates tradeoffs between performanceand cost associated with typical storage media used in combination withcomputers. As shown, removable optical storage devices, such as opticalread-only or read-write disks, generally provide the least expensivealternative for storing large amounts of data. However, single rotatingmagnetic devices, such as hard disk drives used in large numbers ofpersonal computers, provide mass storage that is almost as costeffective as removable optical devices, but with better performance. Inthis context, the term “performance” relates primarily to thereliability and access times associated with the various storage media.As shown in FIG. 1, however, the performance of single rotating magneticstorage devices is increasing less rapidly than the performance of RAIDand solid-state devices.

Although magnetic storage devices are widely used and have becomesignificantly less expensive during recent years, a number oftechnological hurdles have been encountered which threaten to reduce therate at which future improvements in cost and performance will occur.FIG. 2 is a perspective view of a conventional magnetic storage device.Magnetic disk drive 10 includes a rotating magnetic storage medium 12that, as mentioned above, can store tens of gigabytes of data in an areaof only a few square inches. A head gimbal assembly 14 (“HGA”) positionsa recording head 16 with a transducer in close proximity to the surfaceof the magnetic storage medium 12 to enable data to be read from andwritten to the storage medium. An actuator assembly 18 rotates the HGA14 during operation to position the transducer of the recording head 16at the proper location over the rotating magnetic storage medium 12.

One of the most significant problems that have arisen in the effort toimprove capacity and performance in magnetic storage devices is trackfollowing, or the ability to quickly and reliably position thetransducer of the recording head 16 over the appropriate track on themagnetic storage medium 12. In conventional devices, the actuatorassembly 18 includes a voice coil that uses a feedback loop based onservo tracks that are embedded between the data tracks on the magneticstorage medium 12. The track pitch (i.e., the spacing between adjacenttracks) of the storage medium 12 in conventional devices is as low as0.2 microns. At such small track pitches, non-repeatable motions of therotating magnetic storage medium 12, the HGA 14, and the othermechanical components of disk drive 10 make it increasingly difficult toreliably follow the data tracks on the magnetic storage medium. Forexample, in devices having an HGA 14 with a length of 1.5 inches to therecording head 16 and a track pitch of 0.2 microns, the angular positionof the head gimbal assembly needs to have resolution better than 33millionths of an arc second in order to adequately follow the tracks onthe magnetic storage medium 12. Efforts to achieve adequate trackfollowing have included the use of smaller disks for high speed drives,fluid motors for improved damping, and active rotational feedbacksensors using negative feedback algorithms. However, the use of suchtechniques can lead to either the loss of capacity or are only temporarysolutions to this problem, as track pitches continue to decrease.

A closely related problem is that of the settling time and performance,which relates to the ability to stabilize the recording head over atrack. The settling time is dictated by the inertial loads and theexciting resonant frequencies associated with the act of accessing aselected track, the amount of damping in the HGA 14, and the servobandwidth. These factors are generally limited by the resonantfrequencies in the arm of the HGA 14. Thus, settling times have notsignificantly improved in the last several generations of drives in viewof the fundamental limitations on the mechanics of drives that use arecording head 16 controlled by an HGA 14 and an actuator assembly 18,as shown in FIG. 2.

As both the track pitch and the size of sector regions on the magneticmedia used to physically record bits of data have decreased, transducersin disk drives have been required to be positioned closer to the surfaceof the magnetic storage device. A representation of the distance betweenthe transducer and the surface of the magnetic storage medium, referredto as the fly height 22, is shown in FIG. 3. Current fly heights are nowas small as 50 Angstroms (Å) in high capacity disk drives. The flyheight is dictated by the fundamental resolution requirements associatedwith the magnetic storage device, which is a function of the track pitchand the size of the regions on which bits of data are physicallyrecorded. If the fly height becomes too large during operation, thetransducer becomes unable to resolve bits encoded in the storage medium.On the other hand, if the transducer is brought into physical contactwith the optical storage medium, which can be traveling at speeds on theorder of 100 miles per hour, both the transducer and the storage devicecan be damaged.

The fly height has been controlled in conventional devices by improvingthe manufacturing tolerances, by designing a highly rigid and dampenedHGA 14, and by the use of air bearings associated with the recordingheads 16. An air bearing is a cushion or layer of air that developsbetween the surface of the magnetic storage medium and the adjacentsurface of the transducer as the storage medium moves underneath thetransducer.

As noted above, as the fly heights required in magnetic storage deviceshave decreased, the problem of transducer damage from excessive mediacontact has become more pronounced. Current giant magnetoresistance(“GMR”) and tunneling magnetoresistance (“TMR”) transducer heads aresensitive to being damaged if excessive contact with the storage mediumis experienced. One related problem is that conventional transducerdesigns often lead to thermal pole tip protrusion, which occurs when thetransducer is heated and the tip, or pole, of the transducer extends andprotrudes beyond the plane of the transducer. Thermal pole tipprotrusion can aggravate the contact of the transducer with the storagemedium and can lead to increased or more rapid damage of the transducer.

These problems currently facing the magnetic storage device industrythreaten to impede the ongoing progress in reliability, performance, andcost that has been achieved during recent years. Although many of theseproblems can be overcome to some degree using conventional head gimbalassembly designs, it is unlikely that these problems can be successfullyovercome while keeping costs for disk drive users down.

One approach that is currently being developed to lessen the effects ofthe challenges discussed above involves a technique called second stageactuation. Second stage actuation systems use a dual actuation methodfor controlling the horizontal tracking position of the head over aservo mark positioned on the surface of the storage medium. A coarseactuator, similar to a HGA, positions the recording head to a globalposition, and a fine actuator with a single, horizontal degree offreedom at the head positions the head and transducer to a fineposition. While this technique can be adequately practiced in connectionwith previous versions of magnetic storage media, the increased densityon newer discs requires closer tolerances on the fly height, asdiscussed above. As the fly heights of newer storage systems continuallydecrease, second stage actuation technology becomes increasinglyinadequate, particularly in light of the fact that transducerpositioning is limited to adjustment in only the horizontal direction.

Additionally, it is known that previous methods have been attempted tomeasure fly height of a recording head above the surface of a magneticstorage medium. These methods include calculations involvingcapacitance, ratios of certain harmonic amplitudes, and vibrationalaspects of piezo-electric devices mounted on the recording head.However, these methods have proven inadequate in precisely controllingand calibrating fly height and other possible movements of the recordinghead in newer magnetic storage devices.

SUMMARY OF SELECTED EMBODIMENTS OF THE INVENTION

Briefly summarized, embodiments of the present invention are generallydirected to improving the performance and use of magnetic storage media,such as hard disk drives. More specifically, the present invention isdirected to a rotating magnetic storage medium having a recording headthat is bi-directionally controlled with respect to the surface of amagnetic medium. Bi-directional control of the recording head results inimproved head positioning precision, thereby enabling more reliableaccess to data stored on and written to the hard disk drive.

In one embodiment a magnetic storage medium, such as a hard disk drive,is disclosed. The hard disk drive includes a magnetic medium, such as ahard disk, that is accessed by a recording head. The recording head issupported by a head gimbal assembly having a macroactuator that ismovable to coarsely position the recording head with respect to thesurface of the magnetic medium. The recording head is bi-directionallymovable in order to precisely position a transducer of the recordinghead with respect to the magnetic medium surface. This is achieved withan interleaver assembly that is included as a component of the recordinghead and is interposed between a slider body and the transducer.

In one embodiment, the interleaver assembly includes a plurality offlexure beam assemblies that are arranged in a specified configurationin the interleaver so as to constrain movement of the interleaver inspecified directions when a motional force is imposed on it. In brief,upon application of the motional force, the flexures constrain motion ofthe interleaver, and the transducer attached to the interleaver, indesired directions with respect to the magnetic medium surface.

In one embodiment, the motional force is provided by one or more motorassemblies positioned in the interleaver and/or slider body. The motorassemblies, which employ electromagnetic attraction to move theinterleaver assembly, also include a hard magnetic material, such as aferromagnetic substance, that maintains the interleaver assembly, andhence the transducer, in a predetermined nominal position when theelectromagnetic component of the motor assembly is powered off. Thisfurther reduces the amount of energy required to provide the necessarymotional force.

In another embodiment, the motional force to move the interleaverassembly using the plurality of flexure beams is provided byelectrostatic structures. In detail, rigid cantilevered beams containingstatic electrical charges are interposed between stiff flexure beams ofthe flexure beam assemblies. When motion is desired, an electricalsignal is imposed on the stiff flexure beams, which causes interactionwith the charged cantilevered beams, thereby creating the desiredmotional force. In another embodiment, the stiff flexure beams containthe static electrical charges and, when motion is desired, an electricalsignal is imposed on the cantilevered beams to interact with thecharged, stiff flexure beams and provide the motional force.

In one embodiment, piezoelectric structures are alternatively used toprovide the motional force for moving the interleaver assembly. Inbrief, the body of the interleaver assembly includes a plurality ofembedded piezoelectric elements. When transducer motion is desired, anelectrical signal is imposed on one or more of the piezoelectricelements, which causes the piezoelectric element or elements to slightlydeform, causing corresponding deformation of the interleaver assemblymain body. The transducer, being attached to the main body of theinterleaver assembly, is thus moved as well.

In other embodiments, methods are described for preparing,manufacturing, and optimizing the operation of a recording head havingthe interleaver assembly design described above.

In addition, certain structural configurations between the slider bodyand the interleaver assembly of the bi-directional recording head aredisclosed, to provide desired qualities for the head. Among these is theuse of a stepped surface defined on a portion of the interleaverassembly that faces the slider body to enable improved transducermovement.

Additional features and advantages of the invention will be set forth inthe description which follows, and in part will be obvious from thedescription, or may be learned by the practice of the invention. Thefeatures and advantages of the invention may be realized and obtained bymeans of the instruments and combinations particularly pointed out inthe appended claims. These and other features of the present inventionwill become more fully apparent from the following description andappended claims, or may be learned by the practice of the invention asset forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof that areillustrated in the appended drawings. It is appreciated that thesedrawings depict only typical embodiments of the invention and aretherefore not to be considered limiting of its scope. The invention willbe described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 is a graph that depicts relative cost and performance values ofconventional data storage device technologies;

FIG. 2 is a perspective view of a conventional disk drive and headgimbal assembly;

FIG. 3 is a perspective view of a recording head/magnetic storage mediuminterface of a conventional disk drive;

FIG. 4 a is a simplified, exploded view of a portion of a recording headincluding a slider body, an interleaver assembly, and a transducer body,according to one embodiment;

FIG. 4 b is an assembled perspective view of a recording head using thecomponents shown in FIG. 4 a, according to one embodiment;

FIG. 5 a is a front view of an interleaver assembly according to oneembodiment;

FIG. 5 b is a top view of the interleaver assembly of FIG. 5 a;

FIG. 5 c is a cross sectional view of the interleaver assembly takenalong the line 5 c-5 c of FIG. 5 a;

FIG. 5 d is close-up view of a portion of a flexure assembly taken aboutline 5 d of FIG. 5 c;

FIG. 5 e is a top view of the recording head of FIG. 4 b, depictingadditional features thereof;

FIG. 6 is a top view of an interleaver assembly configured according toone embodiment of the present invention;

FIG. 7 a is a simplified top view of the recording head of FIG. 4 b in afirst state, wherein flexures of the interleaver assembly are in anun-flexed position;

FIG. 7 b is a simplified top view of the recording head of FIG. 4 b in asecond state, wherein the flexures of the interleaver assembly are in aflexed position;

FIG. 7 c is a simplified top view of the recording head of FIG. 4 b inanother state, wherein only a portion of the flexures of the interleaverassembly is in a flexed position;

FIG. 8 is a simplified perspective view of a recording head made inaccordance with one embodiment of the present invention;

FIG. 9 is a simplified front view of a flexure region of the interleaverassembly depicted in FIG. 8, showing flexure beams and electrostaticallycharged cantilevered beams in an unactuated state, according to oneembodiment;

FIG. 10 is a simplified front view of the flexure region of FIG. 9,showing the flexure beams in an actuated state;

FIG. 11 a is a simplified front view of an interleaver assembly havingflexure regions as shown in FIG. 9, wherein the flexure beams are in afirst, un-flexed state;

FIG. 11 b is a simplified front view of the interleaver assembly of FIG.11 a, showing the flexure beams in a second, flexed state;

FIG. 11 c is a simplified front view of the interleaver assembly of FIG.11 a, showing the flexure beams in a third, partially flexed state.

FIG. 12 is a simplified front view of a flexure region of an interleaverassembly, containing flexure beams and electrostatically cantileveredbeams in an unactuated state, according to one embodiment;

FIG. 13 a is a simplified front view of a flexure region of aninterleaver assembly, containing flexure beams and electrostaticallycantilevered beams, according to another embodiment;

FIG. 13 b is a simplified front view of a flexure region of aninterleaver assembly, containing flexure beams and electrostaticallycantilevered beams, according to yet another embodiment;

FIG. 14 a is a perspective view of an interleaver assembly containingdiscrete piezoelectric elements in an unactuated state, according to oneembodiment;

FIG. 14 b is a perspective view of the interleaver assembly of FIG. 14a, showing the discrete piezoelectric elements in an actuated state;

FIG. 15 a is a simplified perspective view of an assembled recordinghead including a slider body, the interleaver assembly of FIG. 14 a, anda transducer body, according to one embodiment;

FIG. 15 b is an exploded view of the recording head of FIG. 15 a;

FIG. 16 a is a simplified front view of the recording head of FIG. 15 a,wherein the discrete piezoelectric elements are shown in a first,unactuated state;

FIG. 16 b is a simplified front view of the recording head of FIG. 15 a,wherein both discrete piezoelectric elements are in an actuated state;

FIG. 16 c is a simplified front view of the recording head of FIG. 15 a,wherein only one of the discrete piezoelectric elements is in anactuated state;

FIG. 17 is a top view of a recording head made in accordance with yetanother embodiment of the present invention;

FIG. 18 is a cross sectional view of the recording head of FIG. 17,taken along the line 18-18;

FIG. 19 is a cross sectional view of the recording head of FIG. 17,taken along the line 19-19;

FIG. 20 is a cross sectional/side view of the recording head of FIG. 17,taken along the line 20-20, showing portions of a motor assembly; and

FIG. 21 is a graph showing the relationship between magnetizing forceand magnetization in a ferromagnetic material with respect to the motorassembly of FIG. 20.

DETAILED DESCRIPTION

Reference will now be made to figures wherein like structures will beprovided with like reference designations. It is understood that thedrawings are diagrammatic and schematic representations of presentlypreferred embodiments of the invention, and are not limiting of thepresent invention nor are they necessarily drawn to scale.

FIGS. 1-21 depict various features of embodiments of the presentinvention, which is generally directed to a recording head that usesvarious methods of actuation to move a transducer with respect to amagnetic medium, such as a rotating disk, in a magnetic storage device.Examples of magnetic storage devices can include a hard disk drive usedin one of a variety of electronic products. In particular, structuresand methods are disclosed herein particularly relate to a recording headhaving an integrated, bi-directional micropositioner. Themicropositioner is configured to be selectively moved in two orthogonaldirections with respect to the surface of the magnetic medium, therebyenabling greater precision in positioning a transducer located in themicropositioner near the magnetic medium surface.

Various aspects regarding the structure, calibration, and operation ofrecording heads having an integrated micropositioner are included inU.S. patent application Ser. No. 10/342,920, filed Jan. 13, 2003,entitled “Integrated Recording Head Micropositioner for Magnetic StorageDevices” (“the '920 application”); U.S. patent application Ser. No.10/342,615, filed Jan. 13, 2003, entitled “High Sustained Data RateStorage Devices Having Microactuator” (“the '615 application”); U.S.patent application Ser. No. 10/775,406, filed Feb. 9, 2004, entitled“Method of Calibrating Magnetic Storage Medium Bi-Directional RecordingHead” (“the '406 application”); U.S. patent application Ser. No.10/728,561, filed Dec. 5, 2003, entitled “Self-Servo Writing UsingRecording Head Micropositioner” (“the '561 application”); U.S. patentapplication Ser. No. 10/794,482, filed Mar. 5, 2004, entitled“Integrated Recording Head Micropositioner Using Off-Axis FlexureBending” (“the '482 application”); and U.S. patent application Ser. No.10/818,641, filed Apr. 5, 2004, entitled “Micropositioner Recording Headfor a Magnetic Storage Device” (“the '641 application”). Each of theseapplications is incorporated herein by reference in its entirety.

While FIGS. 2 and 3 illustrate conventional disk drives, these figuresset forth a convention regarding a frame of reference that is useful indescribing the methods of positioning and calibrating the transducers ofthe recording heads. As shown in FIG. 2, a rotating magnetic storagemedium 12 rotates counterclockwise, such that elements on the storagemedium that encode individual bits of data travel under the recordinghead 16 in a direction that is substantially parallel to thelongitudinal axis of the arm of the head/gimbal assembly (“HGA”) 14. Inother words, a particular track of the magnetic storage medium 12, whichis concentric with the circumference of the magnetic storage medium, issubstantially tangent to the longitudinal axis of the HGA 14 when thetrack is positioned under recording head 16. This motion of the magneticstorage medium 12 with respect to the HGA 14 defines a trailing edge orsurface of the recording head 16 that is distal from the axis ofrotation of the HGA 14.

FIG. 3 is a perspective view of the recording head, and shows anelevation of the trailing surface of the recording head 16. In FIG. 3,the motion of the illustrated portion of the magnetic storage medium 12during operation is generally in the y direction, while the orientationof the data tracks of this portion of the magnetic storage medium islikewise substantially in the y direction. As shown in FIG. 3, the zdirection is defined to be perpendicular to the surface of the magneticstorage medium 12. The x direction is defined to be substantiallyperpendicular to or lateral with respect to the orientation of thetracks. In other words, motion in the x direction can cause thetransducer to be laterally moved between tracks or to be centered over atrack; thus movement in the x direction is known as track-to-trackmovement. Because of the small angles involved, the motion of thetransducer can be considered to be a translation in the x direction,regardless of whether the motion is a result of the actuation of themicropositioner integrated into the slider body of the recording head 16or motion associated with the rotation of the HGA 14 about the axis ofrotation of the HGA 14. The y axis is defined to be perpendicular toboth the x and z axes as shown in FIG. 3.

FIG. 3 also illustrates a fly height 22, which is defined to be thedistance in the z direction between the surface 24 of the magneticstorage medium 12 and the adjacent bottom, or air bearing, surface 26 ofthe recording head transducer. FIG. 3 illustrates the general positionof a transducer in region 19 and the relationship thereof to the x, yand z axes and the fly height 22.

The definitions and descriptions of track-to-track, fly height, andrelated concepts as described above are applied in the followingdiscussion in describing various features of embodiments of the presentinvention. Note that the principles of the present invention to bedescribed below can be reliably used with existing recording media aswell as with higher density recording media that will be developed inthe future. Also, the discussion to follow focuses on the interaction ofa recording head with a top surface of a magnetic storage medium. Inother embodiments, however, it should be appreciated that magneticstorage devices having a plurality of recording heads operating inconjunction with a plurality of magnetic storage medium surfaces canalso benefit from the present invention. Thus, the description containedherein is merely illustrative of the broader concepts encompassed by thepresent invention, and is not meant to limit the present invention inany way.

Reference is now made to FIGS. 4 a, 4 b, and 8, which show generalrepresentations of a micropositioning recording head according tovarious embodiments of the present invention. As such, the recordinghead to be described is merely exemplary of those recording heads thatfit within the description herein, and is not meant to confine theinvention to only the illustrated implementations. In particular, arecording head, generally depicted at 30 in FIGS. 4 a and 4 b and at1030 in FIG. 8, forms a component of a magnetic storage device, such asa hard disk drive (not shown) for use in reading and writing data to amagnetic medium. The recording head 30 of the present embodimentgenerally includes a slider body 32, a transducer body 42, and aninterleaver assembly 100. These components cooperate in providingbi-directional actuation of the recording head, and more particularlythe transducer body, with respect to a surface 52 of a magnetic storagemedium, as shown, for example, in FIG. 8.

The interleaver assembly 100 is interposed between the slider body 32and the transducer body 42 and serves as a means by which the transducer43 can be bi-directionally moved with respect to the magnetic storagemedium surface 52. As such, the interleaver assembly 100 of the presentinvention generally includes attachment 104A and 104B regions thatrigidly connect with the slider body 32, a separate main body portion108, and flexure assemblies 106A and 106B that enable the main bodyportion to move with respect to the attachment regions.

With continuing reference to FIGS. 4 a, 4 b, and 8, reference is nowmade to FIGS. 5 a-5 f, which together depict additional detailsregarding the recording head 30 and the interleaver assembly 100,according to one embodiment. As mentioned, the interleaver assembly 100includes the first and second interconnect regions 104A and 104B, thefirst and second flexure assemblies 106A and 106B, and the body portion108. The body portion 108 is indirectly attached to each interconnectregion 104A and 104B via the first and second flexure assemblies 106Aand 106B. As such, the first flexure assembly 106A is attached to andinterposed between the first interconnect region 104A and a centralportion 120 of the body portion 108, while the second flexure assembly106B is attached to and interposed between the second interconnectregion 104B and the central portion 120. According to one embodiment,the flexure assemblies 106A and 106B include a plurality of resilientflexure beams 117, as shown in FIGS. 5 a-5 d, that can deform whensubjected to a sufficient motional force. The flexure beams 117 of eachflexure assembly 106A and 106B are configured such that theirdeformation causes movement of the body portion 108 and transducer 43 inspecified directions with respect to the magnetic medium surface 52. Inone embodiment, flexure of the flexure assemblies 106A and 106B resultsin selective transducer motion in a vertical, fly height direction,which corresponds to movement along the z-axis shown in FIG. 8, and in ahorizontal, track-to-track direction, which corresponds to movementalong the x-axis. Further details regarding the structure and operationof the flexure assemblies 106A and 106B can be found in the '482application.

A number of configurations can be employed in the recording head 30 toprovide the motional force described above for selectively flexing theflexure assemblies 106A and 106B to achieve correspondingmicropositioning movement of the transducer 43. One configurationemploys motor assemblies 130A and 130B, various components of which areshown in FIGS. 5 a-5 e. In brief, each motor assembly 130A and 130Bincludes a magnetic flux source 132 and an inner closure bar 134positioned in the interconnect regions 104A and 104B, respectively, ofthe interleaver assembly 100, as well as a top closure bar 136 andbottom closure bar 138 positioned in the slider body 32. The componentsof each motor assembly 130A and 130B are positioned proximate oneanother, as shown in FIG. 5 e, in order to form an electromagnetic loopwhen one or both motor assemblies are selectively energized, therebyproviding a desired motional force for flexing of the flexure assemblies117, as briefly explained further below, and as discussed in greaterdepth in the '482 application.

Reference is now made to FIGS. 7 a-7 c in describing various detailsregarding the general operation of the interleaver assembly 100. Asmentioned, the body portion 108 of the interleaver assembly 100 isindirectly attached to each interconnect region 104A and 104B via theflexure assemblies 106A and 106B. The flexure assemblies 106A and 106Binclude the plurality of resilient flexure beams 117, as shown in FIGS.5 a, 5 c, and 5 d, that can deform when subjected to a sufficient forceprovided by the motor assemblies 130A and 130B or other suitablecomponent. For example, FIG. 7 a shows the interleaver assembly 100 in anon-actuated state, wherein a gap 118 exists between the central portion120 and a corresponding portion of the slider body 32. In this state,channel gaps 122 also exist between each of the interconnect regions104A and 104B and the body portion 108. In contrast, FIG. 7 b shows theinterleaver assembly 100 in an actuated state, wherein the motorassemblies 130A and 130B have been activated to produce a motional forcevia electromagnetic attraction to cause deformation of both flexureassemblies 106A and 106B. When such deformation of the flexure beams 117occurs, the size of the gap 118 is reduced until contact is made betweenthe central portion 120 and the corresponding portion of the slider body32. In turn, this causes movement of the body portion 108 in a specifieddirection according to the configuration of the flexure beams 117.Correspondingly, because of its attachment to the body portion 108, thetransducer body 42 is also generally moved in the same direction as thebody portion 108, this motion being determined by the configuration ofthe flexure beams 117. Note that both channel gaps 122 are eliminated inthis state.

As noted above, the flexure beams 117 of each flexure assembly 106A and106B are configured such that their deformation causes movement of thebody portion 108 and transducer 43 in a specified direction with respectto the magnetic medium surface 52. In one embodiment, deformation of theflexure assemblies 106A and 106B can result in transducer motion in avertical fly height direction and/or in a horizontal, track-to-trackdirection.

Note that the flexure beams 117 are resilient such that, when themotional force provided by the motor assemblies 130A and 130B isremoved, the flexure beams return to their original position, therebycausing the body portion to return to its original position, as in FIG.7 a.

FIG. 7 c shows partial actuation of the interleaver 100, wherein onlythe second motor assembly 130B is actuated to provide a partial motionalforce. This causes the central portion 120 to contact the correspondingportion of the slider body 32 at an angle, thereby only partly closingthe gap 118. This further illustrates one principle of embodiments ofthe invention, wherein motion of the transducer 43 can be affected inone or more of various ways according to the configuration and/oractuation of the interleaver 100.

Reference is now made to FIGS. 8 and 9, which depict portions of arecording head configured in accordance with one embodiment of thepresent invention. As already discussed, various configurations can beemployed to enable selective flexing of the flexure assembly ofrecording heads discussed herein. Indeed, as illustrated in FIGS. 5 a-5e, motor assemblies 130A and 130B are employed to provide a motionalforce sufficient to enable selective flexing of the flexure assemblies106A and 106B. In contrast, FIGS. 8 and 9 depict another configurationthat can be employed for beam flexure.

In detail, FIG. 8 shows a recording head, generally designated at 1030,including a slider body 1032, a transducer body 1042 housing atransducer 1043, and an interleaver assembly 1100 interconnecting theslider body with the transducer body. The interleaver assembly 1100further includes interconnect regions 1104A and 1104B that are connectedto a central portion 1120 thereof via flexure assemblies 1106A and1106B.

FIG. 9 is a view of a portion of the interleaver assembly 1100, asviewed along the line 9-11 c-9-11 c of FIG. 8. Though FIG. 9 explicitlyshows a portion of only the flexure assembly 1106A, the structuredepicted is representative of the entirety of the flexure assembly 1106Aand the flexure assembly 1106B as well. As illustrated, the flexureassemblies 1106A and 1106B are oriented within a plane that isorthogonal to the surface of a magnetic medium, such as the magneticmedium surface 52 of FIG. 8 and each includes a plurality of flexurebeams 1117 extending between a respective one of the interconnectregions 1104A, 1104B and the central portion 1120. In addition, eachflexure assembly 1106A and 1106B includes a plurality of cantileveredbeams 1400 that also extend between one of the interconnect regions1104A, 1104B and the central portion 1120.

As in previous embodiments, the flexure beams 1117 extend between andattach to both a respective one of the interconnect regions 1104A, 1104Band the central portion 1120. In contrast, the cantilevered beams 1400are each attached only to a respective one of the interconnect regions1104A, 1104B and extend toward, but do not attach to, the centralportion 1120. In other embodiments, the cantilevered beams canalternatively attach to the central portion 1120 and extend toward oneof the interconnect regions 1104A, 1104B, or the cantilevered beams caninclude some beams that attach to the central portion and others thatattach to the interconnect regions.

While the flexure beams 1117 shown in FIG. 9 are resilient such thatthey are able to deform, the cantilevered beams 1400 are constructed tohave a relatively greater stiffness than the flexure beams. Thisconfiguration enables operation of the flexure assemblies 1106A and1106B, to be described below.

In one embodiment, each of the flexure assemblies 1106A and 1106B isconfigured such that there are two or more flexure beams 1117 positionedbetween each cantilevered beam 1400, as shown in FIG. 9. Further, thevarious beams of the flexure assemblies 1106A and 1106B are configuredto assume a specified electrical state during operation of the recordinghead 1030 in order to achieve beam flexure and corresponding transducermovement. In detail, each flexure beam 1117 and cantilevered beam 1400is configured to selectively receive a static electric charge or,alternatively, no charge. For example, FIG. 9 depicts a steady statecondition, wherein each flexure beam 1117 is in a neutral, no chargestate, and each cantilevered beam has a positive static charge. In thissteady state condition, no flexure of the flexure beams 1117 takesplace. Although FIG. 9 displays a positive static charge associated withthe cantilevered beams 1400, a negative charge can alternatively beapplied thereto.

Together with reference to FIGS. 8 and 9, reference is now made to FIG.10. As generally described further above, flexure of the flexure beamsoccurs when a sufficient motional force is applied to the beams. In theillustrated embodiment, the motional force is provided by electrostaticinteraction between the various beams of the flexure assemblies 1106Aand 1106B. When beam flexure is desired, the cantilevered beams 1400 ofone or both flexure assemblies 1106A, 1106B are electrostaticallycharged with a specified polarity, in this case, positive. Note that thecantilevered beams 1400 can be maintained with a specified electrostaticcharge, even when beam flexure is not desired. Selected flexure beams1117 are then charged to a polarity opposite that of the cantileveredbeams 1400, in this case, negative. This opposite polarity charge in theillustrated embodiment is placed on each flexure beam 1117 that isadjacent to and directly above a corresponding cantilevered beam 1400,as shown in FIG. 10. This causes each charged flexure beam 1117 to beattracted to the cantilevered beam 400 directly adjacent thereto,resulting in flexure of each flexure beam. Such flexure in turn resultsin movement of the body portion 1108, as detailed further below. Theextent of flexure beam deformation, and the corresponding body portionmovement, is dependent on the magnitude of the charge that is induced onthe flexure beams 1117, i.e., the greater the magnitude of the charge,the more body portion movement that results.

Note that, in the frame of reference of FIGS. 9 and 10, only the flexurebeams 1117 that are adjacent to and directly above a correspondingcantilevered beam 1400 are charged in the manner described above. Thiscan be done by selectively charging only those flexure beams 1117 thatare properly positioned, or by configuring those beams that are not tobe charged as to be electrically non-conductive. This ensures that eachcharged flexure beam 1117 will be properly attracted to thecorresponding cantilevered beam 1400 adjacent thereto.

Reference is now made to FIGS. 11 a-11 c in describing various detailsregarding operation of the interleaver assembly 1100 of the recordinghead 1030, shown in FIG. 8 using an electrostatic motional forces fortransducer movement in the fly height and track-to-track directions. Asmentioned, the transducer 1043 is positioned in the transducer body1042, which in turn is directly attached to the body portion 1108 of theinterleaver assembly 1100. Also, the center portion of 1120 of the bodyportion 1108 is attached to the flexure assemblies 1106A and 1106B.Thus, movement of the center portion 1120 in response to flexure of theflexure assemblies 1106A, 1106B causes corresponding movement of thebody portion 1108 and the transducer body 1042, and hence, thetransducer 1043. FIGS. 11 a-11 c illustrate the details of flexure beammovement in accordance with the embodiment as illustrated in FIGS. 8-10.

In detail, FIG. 11 a shows the center section 1120 and flexureassemblies 1106A and 1106B of the interleaver assembly 1100 in a first,non-actuated state, wherein the flexure assemblies 1106A and 1106B areun-deflected. In contrast, FIG. 11 b shows the center section 1120 andflexure assemblies 1106A and 1106B of the interleaver assembly 1100 in asecond, actuated state, wherein an electrical charge is imposed on theflexure assemblies 1106A and 1106B, as described above, to produce amotional force and cause deformation of both flexure assemblies 1106Aand 1106B. This in turn causes the center section 1120, and thus thebody portion 1108, to be moved in the fly height direction toward themagnetic medium surface 52. Correspondingly, because of its attachmentto the body portion 1108, the transducer body 1042 is also generallymoved in the same fly height direction as the body portion 1108, therebydesirably adjusting the position of the transducer 1043 in the flyheight direction.

Note that the flexure beams 1117 are resilient such that, when themotional force provided by the electrical signal on the flexure beams isremoved, the flexure beams return to their original position, therebycausing the body portion 1108 to return to its original position, asshown in FIG. 11 a.

FIG. 11 c depicts a partial actuation of the flexure assemblies 1106Aand 1106B of the interleaver assembly 1100, wherein an electrical chargeis imposed only on the first flexure assembly 1106A. This actuationcauses flexure of only the flexure assembly 1106A, which in turn resultsin the deflection of only a portion of the center section 1120 of theinterleaver assembly 1100. The motion of the center portion 1120 istranslated through the body portion 1108 (FIG. 8) and the transducerbody 1042 to the transducer 1043. Movement of the transducer 1043 in atrack-to-track direction results, as may be desired during operation ofthe recording head 1030. More generally, various charge combinations canbe imposed on the flexures 1117 of each flexure assembly 1106A and 1106Bto generate a combination of transducer fly height and track-to-trackmotions.

As shown in the present embodiment, gaps are required between theflexure beams 1117 and cantilevered beams 1400 to achieve transducermotion in the fly height direction. As such, this approach only producesforces of approximately 0.2-0.4 mN. Because of these lower forces,resonant frequencies for interleaver assemblies employing electrostaticcharges are approximately 10 kHz.

Reference is now made to FIG. 12, which depicts another embodiment of anelectrostatic charge-driven interleaver assembly. As in the previousembodiment, the interleaver assembly employs electrostatic charges tocause deflection of a plurality of flexure beams 2117 located in twoflexure assemblies, such as the flexure assembly 2106A shown here, thatextend between and connect with an interconnect region 2104A and acentral portion 2120 of the interleaver assembly.

Additionally, a plurality of cantilevered beams 2400 are interposedbetween the flexure beams 2117, the cantilevered beams being connectedto the interconnect region 2104A such that they extend toward, but donot attach to, the central portion 2120, as before.

In contrast to the previous embodiment, each flexure assembly, such asthe flexure assembly 2106A, is configured such that each cantileveredbeam 2400 is interposed between adjacent pairs of flexure beams 2117.Each flexure beam 2117 of the pair carries an electrical charge oppositethat of the other flexure beam of the pair. In FIG. 12, for instance,each upper flexure beam 2117 carries a positive electrical charge, whilethe lower beam carries a negative charge. When deflection of the flexureassembly 2106A or its corresponding flexure assembly (not shown) in aparticular direction is desired, a charge can be imparted to the variouscantilevered beams 2400. In a first state, shown in FIG. 12, thecantilevered beams 2400 carry no charge; thus no deflection of theflexure beams 2117 occurs. In a second, actuated state, the cantileveredbeams 2400 can be imparted with a positive charge, which will, in turn,cause adjacent flexure beams having a negative charge to be attractedthereto, resulting in a net deflection of the flexure assembly 2106A andcorresponding movement of the central portion 2120 as desired. In yet athird, actuated state, the cantilevered beam can be imparted with anegative charge, which will result in the adjacent positively chargedflexure beams 2117 to be attracted thereto, resulting in a deflection ofthe flexure assembly 2106A in a direction opposite to the second,actuated state, along with corresponding movement in the direction ofthe central portion 2120.

Reference is now made to FIGS. 13A and 13B. Deformation of flexure beamsof an interleaver assembly made in accordance with principles of thepresent invention using electrostatic attraction can be configured inother ways from that shown in the previous figures. FIGS. 13A and 13Bare examples of such alternative configurations. In particular, FIG. 13Adepicts portions of an interleaver assembly, including an interconnectregion 3104A interconnected to a central portion 3120, by a flexureassembly 3106A having a plurality of flexure beams 3117 as in previousembodiments. The flexure beams 3117 in the present embodiment areconfigured as being electrically non-conductive. In addition,cantilevered beams 3400 are shown interposed between the flexure beams3117 and extend both from the interconnect region 3104A and from thecentral portion 3120 such that sets of cantilevered beams, one beamextending from the interconnect region and one beam extending from thecentral portion, are positioned adjacent one another. As before, thecantilevered beams 3400 do not span the entire length between theinterconnect region 3104A and the central portion 3120 such that eachcantilevered beam includes one unattached end, as shown in FIG. 13A.

In order to deform the flexure assembly 3106A, opposing staticelectrical charges can be selectively applied to each beam of theadjacent pairs of cantilevered beams 3400, such as the pair shown inFIG. 13A. Charging of the cantilevered beams 3400 in this manner causesattraction between the two beams such that proper deformation of theflexure assembly 3106A is achieved, which as described before, resultsin desired movement of the transducer (not shown) in specified flyheight and track-to-track motions. As before, though not shown, acorresponding flexure assembly configured like the flexure assembly3106A, is included on an opposing side of the central portion 3120, in aconfiguration similar to that shown in FIG. 8.

FIG. 13B depicts yet another embodiment of an interleaver assemblyemploying electrostatic charges for flexure of a flexure assembly 4106A,as well as a corresponding second flexure assembly (not shown). Indetail, the flexure assembly 4106A includes a plurality of flexure beams4117 extending between and connecting to both an interconnect region4104A and a central portion 4120. Interposed between the flexure beams4117 is a plurality of cantilevered beams 4400. As shown in FIG. 13B,pairs of cantilevered beams 4400 are configured such that onecantilevered beam extends from the interconnect region 4104A while anoppositely disposed beam extends from the central portion 4120. Eachcantilevered beam 4400 of each beam pair includes an unattached end, theends of each cantilevered beam being positioned proximate one another.This configuration of the cantilevered beams 4400 enables oppositeelectrostatic charges to be deposited onto either of the cantileveredbeams of the pair, thereby enabling deformation of the flexure assembly4106A and corresponding movement of the transducer (not shown), as inprevious embodiments.

It should be noted that, in addition to the various embodimentsdescribed herein that employ electrostatic charges for deflection of theflexure assemblies, yet other flexure beam and cantilevered beamcombinations can be devised in accordance with the principles of thepresent invention. As such, the embodiments explicitly described hereshould not be considered limiting of the scope of the present inventionin any way.

Reference is now made to FIG. 14 a-16 c. Deflection of an interleaverassembly in accordance with embodiments of the present invention canalso be accomplished employing piezoelectric principles. FIGS. 14 a and14 b depict various features of one such device. In particular, arecording head, generally designated at 5030, is shown and includes aslider body 5032, a transducer body 5042 (FIGS. 15 a, 15 b), and aninterleaver assembly 5100 interconnecting the slider body and thetransducer body. As in the other embodiments disclosed herein, theinterleaver assembly 5100 is electrically connected to the slider body5032 and the transducer body 5042 so as to enable the transmission ofthe electrical signals therebetween as necessary for recording headoperation.

The connection between the interleaver assembly 5100 and the slider body5032 is such that no physical connection exists between the twocomponents in a region corresponding to an area 5511 located on a face5034 of the slider body. The area 5511 further corresponds to a firstgap 5510 defined on an inner face 5507 of the interleaver assembly 5100.Further, the gap 5510 is in communication with a second gap 504 definedbetween the interleaver assembly inner face 5507 and a trailing face5509 such that the two gaps form an L-shaped gap region. Therelationship between the two gaps 5504 and 5510 can be more clearly seenin FIGS. 15 a and 15 b. The lack of physical connection between theslider body 5032 and the interleaver assembly 5100 in the area 5511,together with the gaps 5504 and 5510, enables for selective deformationof the interleaver to be described below. Again, as shown in FIGS. 15 aand b, the transducer body 5042 is attached to the trailing edge 5509 ofthe interleaver assembly 5100.

As shown in FIGS. 14 a and 14 b, two piezoelectric elements 5500A and5500B are positioned within the interleaver assembly 5100 proximate thegaps 5504 and 5510. The piezoelectric elements 5500A and 5500B arepositioned in the interleaver assembly 5100 such that they are able toeffect deformation of the interleaver assembly, and hence, selectivemovement of a transducer 5043. As such, each piezoelectric element 5500Aand 5500B is positioned in an angled relationship with respect to oneanother, as viewed from the perspective shown in FIG. 14 a. In oneembodiment, the piezoelectric elements 5500A and 5500B can be angled amagnitude of three degrees with respect to one another, but other anglescan also be used, in accordance with the needs of the particularapplication. Further, each piezoelectric element 5500A and 5500B isindependently connected to an electrical source such that biasing ofeach element can selectively occur independently of one another toeffect transducer movement. Each piezoelectric element can take avariety of forms, such as singulated elements, deposited films, oranother suitable form.

With continuing reference to FIGS. 14 a-15 b, reference is now made toFIGS. 16 a-16 c in describing operation of the recording head 5030 ofthe present embodiment. Generally, a small electrical potential imposedon a piezoelectric element will cause the element to slightly deform.Thus, when movement of the transducer 43 is desired, an electricalvoltage is placed on one or both piezoelectric elements 5500A and 5500B.The resulting slight deformation of one or both energized piezoelectricelements 5500A and 5500B causes a net force generally directed in the z-and x-axis directions. The interleaver assembly 5100, which houses thepiezoelectric elements 5500A and 5500B, is deformed in response to thenet forces provided by the piezoelectric elements, by virtue of the gaps5504 and 5510, and the nature of the attachment of the interleaverassembly to the slider body 5032 about the area 5511. This ultimatelyresults in a movement of a portion of the trailing face 5509 in thez-axis (fly height) direction, which as shown in FIG. 14 b isaccompanied by a slight widening of the central portion of the gap 5504.Similar operations can be performed to cause deformation in the x-axis(track-to-track) direction, as explained below.

With continuing reference to FIGS. 14 a-15 b, reference is now made toFIGS. 16 a-16 c in describing various details regarding operation of therecording head 5030 and the interleaver assembly 5100 usingpiezoelectric motional forces, in causing the transducer 5043 to move inthe fly height and track-to-track directions. As mentioned, thetransducer body 5042, which houses the transducer 5043, is directlyattached to the trailing surface 5509 of the interleaver 5100. FIG. 16 ashows the interleaver assembly 5100 in a non-actuated state, wherein thepiezoelectric elements 500A and 500B are not activated and no deflectionof the gap 5504 or the interleaver bottom surface 5513 is present. Incontrast, FIG. 16 b shows the interleaver assembly 5100 in an actuatedstate, wherein separate electrical signals are provided equally to bothpiezoelectric elements 5500A and 5500B, as described above, to produce amotional force and cause corresponding equal deformation of thepiezoelectric elements. As explained, deformation of the piezoelectricelements 550A and 5500B results in corresponding deformation of aportion of the interleaver assembly 5100, including the gap 5504, and aportion 5502 of the interleaver assembly disposed between the gap andthe bottom surface 5513. Deformation of the interleaver assembly in thismanner is in a downward, z-axis (fly height) direction. Correspondingly,because of its attachment to the trailing surface 5509 of theinterleaver assembly 5100, the transducer body 42, and hence, thetransducer 5043 itself, is also moved in the fly height direction, asdesired. The distance moved by the transducer 5043 in the fly heightdirection is dependent on the magnitude of the actuation signals imposedon the piezoelectric elements 5500A and 5500B; the greater the signalmagnitude, the greater the resulting transducer movement.

Note that the piezoelectric elements 5500A and 5500B are positioned inthe interleaver assembly 5100 as to function in a resilient manner suchthat, when activation of the piezoelectric elements is terminated,deformation of the elements cease, and the interleaver assembly and thetransducer body 5042 to return to their original positions, as shown inFIG. 16 a.

FIG. 16 c shows the interleaver assembly 5100 in a partially actuatedstate, wherein an electrical signal has been imposed only on the secondpiezoelectric element 5500B to provide a partial motional force. Thiscauses only a portion of the interleaver assembly 5100 to be deflectedin the z-axis, fly height direction. This partial deflection results ina slight rotation of the interleaver assembly portion 5502 about they-axis, as represented by the coordinate axes in FIGS. 16 a-c. Thetransducer body 5042 is also rotated about the y-axis. Rotation of thetransducer body 5042 equates to movement of the transducer 5043 in atrack-to-track direction, as shown in FIG. 16 c, which provides forselective microadjustment of the transducer with respect to a magneticmedium surface (FIG. 8), in accordance with principles of the presentinvention. More generally, it is seen that a combination of actuationsignals can be used with one or both piezoelectric elements 5500A and5500B to desirably generate a combination of fly height andtrack-to-track motions.

In one embodiment, each piezoelectric element 5500A and 5500B has alength of approximately 500 microns and is angled with respect to theother piezoelectric element by approximately three degrees. Such aconfiguration yields transducer fly height motion in a range of lessthen 10 microns and track-to-track motion in a range of less than onemicron, with the resonant frequencies of the piezoelectric devicesexceeding approximately 50 kHz. Such motions can be optimized bypositioning the piezoelectric elements 5500A and 5500B at relativelyshallow angles with respect to one another and by minimizing thestiffness of the piezoelectric elements.

Reference is now made to FIGS. 17-19, which depict various features ofanother embodiment of the present invention. In detail, FIG. 17 showsportions of a recording head, generally designated at 6030, including aslider body 6032, a transducer body 6042 having a transducer disposedtherein, and a wafer assembly 6100.

In greater detail, the wafer assembly 6100 includes a motor segment 6102and a flexure segment 6103. FIG. 18 shows various features of theflexure segment 6103, including interconnect regions 6104, flexureassemblies 6106 that each include a plurality of flexure beams 6117, abody portion 6108, and a central portion 6120 of the body portion.

FIG. 19 shows various features of the motor segment 6102, includingvarious contact pads 6140B that are employed in electrically connectingthe motor segment with the flexure segment 6103. The motor segment 6102attaches to the flexure segment 6103 in relation to the slider body 6032as shown in FIG. 17. Further details regarding the structure andfunction of the recording head 6030 and its various components inproviding bi-directional transducer movement can be found in the '641application.

FIGS. 18 and 19 further depict various components of a motor 6130including, on the flexure segment 6103, a pair of closure bars 6134positioned on the central portion 6120 and, on the motor segment 6102, apair of magnetic flux sources, in this embodiment, toroidal coils 6132.As with other embodiments, the motor 6130 is employed to provide amotional force to the plurality of flexure beams 6117 located in bothflexure assemblies 6106. In brief, selective activation of the toroidalcoils 6132 of the motor segment 6102 causes an electromagneticattractive force to be imposed on the closure bars 6134 of the flexuresegment 6103, which closure bars are, in the present embodiment,composed of a metallic material that is suitable for electromagneticattraction to the toroidal coils 6132. This results in movement of thecentral portion 6120 and the body portion 6108 toward the motor segment6102 via flexure of the plurality of flexure beams 6117. Movement of thebody portion 6108 in turn results in specified movement of thetransducer body 6042 attached thereto. Thus, activation of the toroidalcoils 6132, or other suitable components, can be customized to providebi-directional movement of the transducer body 6042 in track-to-trackand fly height directions with respect to the surface of a magneticstorage medium (such as that shown in FIG. 8).

With continuing reference to FIGS. 17-19, reference is now made to FIGS.20 and 21. In particular, FIG. 20 depicts a cross sectional/side view ofthe motor segment 6102 and flexure segment 6103 along the lines 20-20 ofFIG. 17. In detail, FIG. 20 shows side views of an adjacent pair of onetoroidal coil 6132 and one closure bar 6134. In accordance with thepresent embodiment, each of the closure bars 6134 includes a magneticportion 6200 positioned centrally along the closure bar. The magneticportion 6200 is included in the closure bar to assist in the operationof the closure bar within the motor 6130 during operation of theinterleaver assembly 6100 in bi-directionally positioning thetransducer, as will be explained.

In one embodiment, the magnetic portion 6200 is composed of a hard, orpermanent magnetic material that is not easily demagnetized, such asSmCo. In other embodiments, however, other magnetic materials, includingsofter or harder magnetic materials can also be employed in accordancewith the needs of a particular application. In addition, though shown inFIG. 20 to be centrally positioned on the closure bar, the magneticportion 6200 can be positioned on other portions of the closure bars,can have respectively different positions on each closure bar, or can bepositioned apart from the closure bars. In yet other embodiments, eachclosure bar can have more than one magnetic portion. Though they aredescribed herein in connection with the recording head shown in FIG. 17,it is nonetheless appreciated that the magnetic portions of the presentembodiment can also be included as components of the other recordingheads described herein and of the recording heads described in theaforementioned applications incorporated herein by reference.

The mass of each magnetic portion 6200 is determined by several factors,including the attractive force to be supplied by each magnetic portion,and the type of material from which the magnetic portion is formed.

By using a hard magnetic material that can retain its magnetism, a levelof attractive force can be maintained between the closure bars 6134 andthe toroidal coils 132 even when no external power is activated. Thisenables a relatively smaller gap 6115 to be maintained when the motor6130 is unactuated. Moreover, when the motor 6130 is actuated to drawthe central portion 6120 of the body portion 6108 toward the motorsegment 6102 during transducer positioning, relatively less energy isrequired to close the gap 6115 because the initial spacing of the gap isalready smaller than it otherwise would be without the additionalmagnetic force provided by the magnetic portion 6200.

FIG. 21 illustrates details regarding the magnetic properties of a hardmagnetic material that can be used to form the magnetic portion 6200shown in FIG. 20. In general, when a ferromagnetic material is subjectedto a continuously increasing magnetizing force (H), the material becomesmagnetized and retains some of the magnetization (B) when themagnetizing force is removed, as shown in the hysteresis loop depictedat 6300 in FIG. 21. This retained magnetization is also known as remnantmagnetization. The amount of retained or remnant magnetization dependson the magnitude of the original magnetizing force. For instance, if theferromagnetic material is initially exposed to a magnetization force ofH₁ as shown on FIG. 9, then the material will retain a magnetic fieldequal to B₁ when the magnetization force is removed. Similarly, if theferromagnetic material is initially exposed only to a lowermagnetization force of H₂ as shown on FIG. 9, then the material willretain a magnetic field equal to B₂ when the magnetization force isremoved, which is proportionately lower than B₁. Thus, a desired levelof retained magnetization can be obtained by simply initially exposingthe material to a particular level of magnetization force.

In one embodiment, calibration of the magnetic portion-equipped motor6130 is necessary, and can proceed as explained here. During manufactureof the recording head, such as the recording head 6030 shown in FIG. 17,the motor 6130 is constructed as disclosed in the '641 application, orby another suitable process. During motor assembly, the magneticportions 6200 are added to each closure bar 6134, as shown in FIG. 18.

Next, a lapping process can be performed to properly shape thetransducer body 6042. During lapping, the transducer (not shown) isbrought into full contact with a lapping surface by energizing thetoroidal coils 6132 of the motor 6130 with an electrical current. Thiscauses the toroidal coils 6132 to become fully magnetized, therebyinducing a corresponding magnetizing force on the closure bars 6134. Themagnetizing force imposed on the closure bars 6134 is represented on thehysteresis loop 6300 at H₁ on FIG. 9. As a result of this magnetizingforce, the magnetic portion 6200 of each closure bar 6134 becomesmagnetized and retains after the termination of toroidal coilenergization a remnant magnetization corresponding to B₁ on FIG. 9.

Once the lapping process is complete, the toroidal coils 6132 are againenergized, but with a bias opposite that used during the initialenergization discussed above. This results in full separation of thetransducer from the lapping surface as well as the induction of amagnetizing force on the closure bars 6134 corresponding to −H₁ on FIG.9. The magnetization of the hard magnetic material 6200 also changes asa result, retaining a remnant magnetization corresponding to −B₁ on FIG.9 once energization of the toroidal coils 6132 in this step interminated.

At this point, an optimum rest-state transducer fly height with respectto the surface of the magnetic storage medium surface (not shown) isdetermined, and a corresponding remnant magnetization value for themagnetic portion 6200 of the closure bars 6134 that will maintain thetransducer at the optimum fly height when the toroidal coils 6132 arenot energized is calculated. An electrical current that corresponds withthe corresponding remnant magnetization value is then provided to thetoroidal coils 6132 sufficient, which in turn generates themagnetization force required to induce the calculated amount of remnantmagnetization on the magnetic portions 6200. When the toroidal coilcurrent is subsequently removed, the magnetic portions 6200, and hencethe closure bars 134, retain the correct amount of magnetization tomaintain the gap 6155 and sustain the transducer at the desiredrest-state fly height.

Note that various steps in addition to or alternative to those describedabove can be employed to calibrate the magnetic portions, according toneed and the particular configuration thereof. Further, though thecalibration of the magnetic portions is performed in connection with alapping process here, in other embodiments, such calibration can occurindependent of other recording head manufacturing or assembly processes.

In one embodiment wherein the magnetic portions are composed of a hardmagnetic material, the length of the closure bars is minimized overclosure bars not including magnetic portions as the permeability of thehard magnetic material is typically much lower than that of materialscommonly used in forming closure bars, such as permalloy, for instance.In one embodiment the material from which the magnetic portions arecomposed possesses a low squareness, which enables the remnant magneticstrength to remain unchanged over the range of currents that will beused in connection with operation of the motor. This further ensures alinear range of currents can be used for actuation of the motor.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrative,not restrictive. The scope of the invention is, therefore, indicated bythe appended claims rather than by the foregoing description. Allchanges that come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

1. A recording head for use in a magnetic storage device having arotating magnetic medium, comprising: a slider body; a transducer bodycontaining a transducer; an interleaver assembly comprising: first andsecond interconnect regions, the first and second interconnect regionsconnected to the slider body; a body portion having a central portionextending between the first and second interconnect regions, the bodyportion being connected to the transducer body; and first and secondflexure assemblies that respectively interconnect the first and secondinterconnect region with the central portion; the first and secondflexure assemblies each including: a plurality of resilient flexurebeams that extend between and attach to a respective one of the firstand second interconnect regions and the central portion; and a pluralityof cantilevered beams that extend between a respective one of the firstand second interconnect regions and the central portion; wherein eachcantilevered beam includes: a first end that attaches to one of thefirst interconnect region, the second interconnect region, and thecentral portion; and an unattached second end; wherein each cantileveredbeam and each flexure beam is configured to be selectively andelectrically charged to provide a motional force to selectively move atleast one of the first and second flexure assemblies and causecorresponding movement of the transducer, wherein selective movement ofat least one of the first and second flexure assemblies causescorresponding movement of the transducer with respect to both the sliderbody and a surface of the magnetic medium.
 2. A recording head asdefined in claim 1, wherein the cantilevered beams are configured to becharged with a static electric charge.
 3. A recording head as defined inclaim 1, wherein each cantilevered beam is interposed between aconductive flexure beam and a nonconductive flexure beam.
 4. A recordinghead as defined in claim 1, wherein the cantilevered beams arerelatively stiff with respect to the flexure beams.